fix(cstor-restore): fixing restore api to return failure if cstorrestore is in invalid state

[mynktl]

Why is this PR required? What issue does it fix?:
This PR is required to fix the issue #1677.

What this PR does?:
This PR updates the REST api for cstore restore to report failure if cstorrestore resource is in invalid state.
There is one additional change in restore controller in cstor-pool-mgmt to ignore the update if cstorrestore CR is having state Done or Failed

Does this PR require any upgrade changes?:
No

If the changes in this PR are manually verified, list down the scenarios covered::

• Restart the cstor-pool pod when restore is in-progress state
  - outcome is restore failed
• Restart the cstor-pool pod before it process the cstorrestore CR
  - outcome is restore failed
• Restart the cstor-pool pod once it update the cstorrestore CR to init state
  - outcome is restore failed
• Restart the cstor-pool pod once the restore completes
  - outcome is cstorrestore status remains same

Checklist:

• Fixes #restore completed successfully but one of the replica was not having the snapshot restored #1677
• Has the change log section been updated? yes
• Commit has unit tests: no
• Commit has integration tests: no

Signed-off-by: mayank mayank.patel@mayadata.io